export default{
    getScrollTop:function (){
        　　var scrollTop = 0, bodyScrollTop = 0, documentScrollTop = 0;
        　　if(document.body){
        　　　　bodyScrollTop = document.body.scrollTop;
        　　}
        　　if(document.documentElement){
        　　　　documentScrollTop = document.documentElement.scrollTop;
        　　}
        　　scrollTop = (bodyScrollTop - documentScrollTop > 0) ? bodyScrollTop : documentScrollTop;
        　　return scrollTop;
        },
        getScrollHeight:function (){
            　　var scrollHeight = 0, bodyScrollHeight = 0, documentScrollHeight = 0;
            　　if(document.body){
            　　　　bodyScrollHeight = document.body.scrollHeight;
            　　}
            　　if(document.documentElement){
            　　　　documentScrollHeight = document.documentElement.scrollHeight;
            　　}
            　　scrollHeight = (bodyScrollHeight - documentScrollHeight > 0) ? bodyScrollHeight : documentScrollHeight;
            　　return scrollHeight;
        },
        getWindowHeight:function getWindowHeight(){
            　　var windowHeight = 0;
        　　if(document.compatMode == "CSS1Compat"){
        　　　　windowHeight = document.documentElement.clientHeight;
        　　}else{
        　　　　windowHeight = document.body.clientHeight;
        　　}
        　　return windowHeight;
        }
}


        //滚动条在Y轴上的滚动距离
        
    //文档的总高度 
    
    //浏览器视口的高度
    


// 